A 3.3 Ohm Resistor produces 33.1 nV from 20 Hz to 20 KhzAlso what does the simulator tell us for 3.3Ω?
Self gets a 6.4 dB NF at 3.3Ω with his 3X 2N4401 MC preamp.
With R collector 1K, noise is:
Rs 3.3 / Rg 3.3 : 63.1 nV NF=5.6 dB
Rs 3.3 / Rg 2 : 59.4 nV NF=5.1 dB
Rs 3.3 / Rg 1 : 52.6 nV NF=4.0 dB
With R collector 500 Ohm, noise is:
Rs 3.3 / Rg 3.3: 56.8 nV NF=4.7 dB
Rs 3.3 / Rg 2 : 52.6 nV NF=4.0 dB
Rs 3.3 / Rg 1 : 49.1 nV NF=3.4 dB
So in all cases this circuit beats the Self design.
Hans